Central body obesity, impaired glucose tolerance and diabetes are common among Hispanic women of childbearing age. These conditions are associated with maternal complications including cesarean section and diabetes after pregnancy, and with fetal complications including macrosomia, birth injuries, obesity and metabolic abnormalities in subsequent life. This study examines the hypothesis that the extent and impact of central body obesity and metabolic abnormalities among pregnant Hispanic women results in higher birth weights than would be predicted based on models of risk that do not include these measures. Since fetal overgrowth secondary to intrauterine over nutrition does not reflect normal processes of growth and maturation, we also expect to find a greater incidence of maternal and newborn complications and metabolic abnormalities compared to infants in the same birth weight distribution born to mothers without these abnormalities. This is a prospective community-based study of a cohort of 700 Hispanic mother-infant pairs in southwest Detroit. The prevalence, distribution and impact of maternal central body obesity and metabolic abnormalities on birth weight and adverse maternal and newborn outcomes will be estimated after accounting for gestational age, prepregnancy BMI, pregnancy weight gain, sociodemographic characteristics, other maternal health conditions and prenatal care. Variables will be derived from maternal anthropometry and metabolic assays of blood samples collected for the study during prenatal care, along with prenatal, obstetric and newborn medical records. The proposed research should contribute to understanding the interactions between maternal and infant status, including the consequences of processes affecting fetal growth. Study results should be applicable to designing appropriate prenatal screening and treatment strategies that will improve quality of care and ultimately maternal and infant outcomes in this and other high risk populations.